I think you need to add the repeating pattern to the left and right working your way outward to get to your desired size. I'm a newbie and I want to tackle this next. Someone pointed me to this free link library and search for the book braided bardello.
https://openlibrary.org/
That book has charts (similar to an excel document). That you can follow to get an idea of what widths achieve the "rise" and "fall". Each column ranges between 1/4" to 3 1/2" at 1/4" increments. Meaning to achieve a slow fall or rise is the widest at 3 1/2" column and the quick fallor rise would use the smallest widths 1/4" in succession.